For example, there are known various medical instruments provided with a valve element such as a tube body guiding device for medical use that guides a tube body like a catheter for angiographies into a blood vessel.
Examples of a conventional valve element include a valve element consisting of a cylindrical elastic body in which a straight slit opened to (reaching) both end faces is formed, a valve element consisting of a cylindrical first elastic body in which a through-hole is formed and a cylindrical second elastic body in which a Y-shaped slit opened to both end faces is formed, and the like.
However, with the aforementioned valve element, the slit may open to form a gap between the slit and the tube body, causing leakage of liquid, particularly when the tube body is inserted and pulled out.
In addition, in the case in which the tube body is inserted for a long period, the valve element is deformed into a shape with the slit opened, whereby the slit does not close even after the tube body is pulled out and leakage of liquid is caused.
In order to suppress such leakage of liquid, a width of the slit only has to be reduced. However, if the width of the slit is reduced, a frictional resistance at the time when the tube body is inserted or pulled out increases, which makes operation for inserting or pulling out the tube body difficult.
Thus, in order to solve such a problem, a valve element consisting of a cylindrical elastic body is proposed in which a slit opened to (reaching) only one end face and a slit crossing with this slit in the inside of the valve element and opened to only the other end face (JP 2-949 B) are formed.
However, the aforementioned JP 2-949 B does not disclose an idea of deforming the valve element.
The inventor has found that, by deforming a valve element such that inner surfaces of one slit are brought into press contact with each other, liquid tightness can be increased and leakage of liquid can be prevented more surely without damaging operability of connection of a connector or the like.
It is a first object of the present invention to provide a valve element that is simple in structure, easy in operation, serviceable for a long period, and capable of preventing leakage of liquid surely.
In addition, on a site of medical care, at the time of an operation or at the time of hospital treatment, in the intravenous hyperalimentation, and the like, a catheter or a needle is inserted into a vein to perform infusion with drip injection.
In various types of infusion, in the case in which other drug solution or the like is injected, the injection is performed in parallel with the infusion or suspending the infusion. A method usually used as this method is to provide in advance a mixing and injecting section that is capable of connecting an infusion line or syringe of another route in the middle of an infusion route, and inject drug solution or the like via this mixing and injecting section.
As components used in this mixing and injecting section, there are kwon a rubber tube for mixing and injection, a liquid mixing and injecting device such as a Y site (also referred to as T-shaped tube) or a three-way cock, and a multiple cock (manifold) consisting of coupled three-way cocks.
In addition, a method also used in an artery line for the purpose of continuously monitoring an arterial pressure is to provide in advance a branching section having substantially the same action as the mixing and injecting section in the middle of the line and perform blood collection or the like from the branching section every time it is necessary.
Among the components used in the mixing and injecting section, the most primitive rubber tube for mixing and injection is pierced by a syringe with needle or the like and used. Thus, it is likely that a doctor or a nurse (hereinafter referred to as medical personnel) pricks his/her finger with the needle by mistake. In addition, if the rubber tube for mixing and injection is connected for a long period, there are problems in that drug solution (liquid) tends to leak easily, it is hard to secure in the case of mixing and injection for a long term, drug solution easily leaks when centesis is repeated (low in centesis resistance). However, the rubber tube for mixing and injection is still used currently because it is inexpensive.
In recent years, for the purpose of preventing pricking by mistake of medical personnel, a mixing and injecting port with valve has been developed which is provided with an open-closable valve of rubber in a mixing and injecting port and can be connected to a luer tip of a syringe or an extension tube without using a needle or can be connected using a blunt needle having an external diameter smaller than that of a luer tip.
However, in the aforementioned mixing and injecting port with valve, it is necessary to provide a slit communicating inner and outer faces of the valve therein, press the slit by a strong force to warp largely and close. Thus, the mixing and injecting port becomes complicated in structure and expensive. In addition, when it is used for a long period, the valve is deformed and the slit does not close sufficiently due to the deformation, thereby causing leakage of liquid. The mixing and injecting port with valve still has such a lot of problems.
In addition, a three-way cock usually has a structure of a female luer connector in a mixing and injecting section, and has an advantage in that it can be connected to a male luer connector of a syringe or an infusion line without using a needle. In addition, it has a function of switching an injection route such as injecting another drug solution simultaneously with injecting main drug solution or suspending injection of main drug solution to perform only side-injection. Thus, the three-way cock is used most frequently because it is convenient.
However, in the aforementioned three-way cock, there is a problem in that, if the cock is closed, since a part where drug solution does not flow (dead space) exists in the female luer and the female luer does not have a rubber septum for shutting the inside thereof from the outside, it is likely that fallen bacteria or the like in the air deposit on the female luer and, after connecting the female luer, the bacteria tend to propagate and contaminate a patient body.
Since there is a Y-shaped space for switching a flow path inside a cock of the three-way cock, if the three-way cock is closed in one direction, a part where drug solution does not easily flow is generated. If a few three-way cocks are connected in series to be used as a multiple cock, since there is a step in a connecting part, irregularity tends to occur in a flow of drug solution. Thus, there are inconveniences in that, when a small amount of drug solution is continuously injected accurately, the drug solution is diluted in the part where it does not easily flow or, when it is expected that the entire amount of drug solution is finished to be side-injected, the drug solution remains in the step or inside the cock and it takes time to flow the entire amount.
Moreover, since drug solution hardly spreads to such a part where drug solution does not easily flow, a step or a dead space, there is also a problem in that work for removing the air in a line before connecting an infusion line to a patient (priming) is made complicated.
The above-mentioned problems are the same for the conventional Y site to which a rubber septum is attached and a new mixing and injecting port that is improved such that a blunt needle or a male luer connector can be inserted for the purpose of preventing pricking by mistake of medical personnel.
It is a second object of the present invention to provide a mixing and injecting device that is simple in structure, capable of being operated easily and safely, serviceable for a long period, and capable of preventing leakage of liquid surely.
In addition, since the above-described mixing and injecting section is prepared in a number set in advance, there may not be the enough number of them.
In such a case, a port for side-injection that is not a main flow path must be additionally connected, which is time consuming. In addition, since liquid is not always flown to this port for side-injection, it is necessary to completely flow a remaining drug solution using, for example, saline or the like after drug solution is side-injected, which is time consuming and easily causes propagation of bacteria if the saline is stayed for a long time. Thus, it is likely that a large amount of propagated bacteria are injected into a patient when the drug solution is injected again.
It is a third object of the present invention to provide a tube that is simple in structure and in which a connection port can be easily provided, if necessary, a tube jointing device, a connection port manufacturing device, and a tube jointing system.